Si51219
T HREE O UTPUTS F ACTORY P R O GRA MM A B LE C LOCK
G ENERATOR
Features
Generates up to 3 CMOS clock Separate voltage supply pins
outputs from 3 to 200 MHz
VDD = 2.5 to 3.3 V
Accepts crystal or reference
VDDO= 1.8 to 3.3 V (VDDO ≤ VDD)
clock input
0.25% to 1.0% Spread Spectrum
3 to 166 MHz reference clock input
(Center Spread)
8 to 48 MHz crystal input
Low cycle-cycle jitter
Programmable FSEL, SSEL,
Programmable output rise and
SSON, PD, and OE input
fall times
functions
8-pin TSSOP package
Low power dissipation
Applications
Crystal/XO replacement
EMI reduction
Portable devices
Digital still camera
IP phone
Home gateway
Ordering Information:
See page 9.
Pin Assignments
Description
The factory programmable Si51219 is a low power, small footprint and
frequency flexible programmable clock generator targeting low power, low
cost and high volume consumer and embedded applications. The device
operates from a single crystal or an external clock source and generates
1 to 3 outputs up to 200 MHz. They are factory programmed to provide
customized output frequencies, control inputs and ac parameter tuning
like output drive strength that are optimized for customer board condition
and application requirements. A separate VDDO supply pin supports
clock output at a different voltage level.
VDD
1
XOUT
2
XIN/CLKIN
3
SSCLK1/REFCLK
FSEL/SSEL/SSON/
OE2
4
8 VDDO
7 SSCLK3
Si51219
SSCLK2/REFCLK_D
6 FSEL/SSEL/SSON/
PD/OE1
5 VSS
Patents pending
Functional Block Diagram
XOUT 2
VDD0 8
VDD 1
4
PLL with
Modulation
Control
XIN/
3
CLKIN
To Pin 7
V-REG
To Core
Programmable
Configuration
Register
To Pin 4 and Pin 6
VSS 5
Preliminary Rev. 0.7 1/12
Buffers,
Dividers,
and
Switch
Matrix
6
SSCLK1/
REFCLK/
0E2/FSEL/
SSEL/SS0N
SSCLK2/
REFCLK_D
0E1/FSEL/
SSEL/SS0N/PD
7 SSCLK3 (VDD0)
Copyright © 2012 by Silicon Laboratories
Si51219
This information applies to a product under development. Its characteristics and specifications are subject to change without notice.
Si51219
2
Preliminary Rev. 0.7
Si51219
TABLE O F C ONTENTS
Section
Page
1. Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
2. Design Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
2.1. Typical Application Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
3. Functional Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
3.1. Input Frequency Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
3.2. Output Frequency Range and Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
3.3. Programmable Modulation Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
3.4. Programmable Spread Percent (%) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
3.5. SSON or Frequency Select (FSEL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
3.6. Power Down (PD) or Output Enable (OE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
4. Pin Descriptions: 8-Pin TSSOP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
5. Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
6. Package Outline: 8-pin TSSOP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Preliminary Rev. 0.7
3
Si51219
1. Electrical Specifications
Table 1. DC Electrical Specifications
(VDD = 2.5 V ± 5%, or VDD = 3.3 V ± 10%, TA = 0 to 70 oC)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
VDD
VDD=3.3 V ±10%
2.97
3.3
3.63
V
VDD=2.5 V ±5%
2.375
2.5
2.625
V
VDDO
VDDO ≤ VDD
1.71
—
3.6
V
Output High Voltage
VOH
IOH= –4 mA,
VDDX=VDD or VDDO
VDDX-0.5
—
—
V
Output Low Voltage
VOL
IOL= 4mA,
—
—
0.3
V
Input High Voltage
VIH
CMOS level
0.7 VDD
—
—
V
Input Low Voltage
VIL
CMOS level
—
—
0.3 VDD
V
Operating Supply Current
IDD
FIN=12 MHz, CLKOUT1
=12 MHz, CLKOUT2/3
=24 MHz, CL=0, VDD=3.3 V
—
6
—
mA
Nominal Output Impedance
ZO
—
30
—
Operating Voltage
RPUP/RPD
Pin 6
—
150k
—
Input Pin Capacitance
CIN
Input Pin Capacitance
—
3
5
pF
Load Capacitance
CL
Clock outputs < 166 MHz
—
—
15
pF
Clock outputs > 166 MHz
—
—
10
pF
Internal Pull-up/Pull-down
Resistor
4
Preliminary Rev. 0.7
Si51219
Table 2. AC Electrical Specifications
(VDD = 2.5 V ± 5%, or VDD = 3.3 V ± 10%, TA = 0 to 70 oC)
Parameter
Symbol
Condition
Min
Typ
Max
Unit
Input Frequency Range
FIN1
Crystal input
8
—
48
MHz
Input Frequency Range
FIN2
Reference clock Input
3
—
166
MHz
Output Frequency Range
FOUT
SSCLK1/2/3
3
—
200
MHz
Frequency Accuracy
FACC
Configuration dependent
—
0
—
ppm
DCOUT
Measured at VDD/2
45
50
55
%
Input Duty Cycle
DCIN
CLKIN, CLKOUT through PLL
30
50
70
%
Output Rise Time
tr
CL=15 pF, 20 to 80%
—
1
3.0
ns
Output Fall Time
tf
CL=15 pF, 20 to 80%
—
1
Output Duty Cycle
Period Jitter
3.0
ns
*
PJ1
SSCLK1/2/3, three clocks running,
VDD=3.3 V, CL=15 pF
—
150
—
ps
CCJ1
SSCLK1/2/3, three clocks running,
VDD=3.3 V, CL=15 pF
—
100*
—
ps
Power-up Time
tPU
Time from 0.9 VDD to valid frequencies
at all clock outputs
—
1.2
5.0
ms
Output Enable Time
tOE
Time from OE raising edge to active at
output SSCLK1/2 (asynchronous)
—
15
—
ns
Output Disable Time
tOD
Time from OE falling edge to active at
output SSCLK1/2 (asynchronous)
—
15
—
ns
Min
Typ
Max
Unit
–0.5
—
4.2
V
Cycle-to-Cycle Jitter
*Note: Jitter performance depends on configuration and programming parameters.
Table 3. Absolute Maximum Conditions
Parameter
Symbol
Condition
Main Supply Voltage
VDD
Input Voltage
VIN
Relative to VSS
–0.5
—
VDD+0.5
V
Temperature, Storage
TS
Non-functional
–65
—
150
°C
Temperature, Operating Ambient
TA
Functional, C-Grade
0
—
70
°C
Temperature, Junction
TJ
Functional, power is
applied
—
—
125
°C
Temperature, Soldering
TSol
Non-functional
—
—
260
°C
Dissipation, Junction to Case
ØJC
Independent of air flow
—
—
36
°C/W
Dissipation, Junction to Ambient
ØJA
Still air
—
181
—
°C/W
ØJA
1m/s air flow
—
100
—
°C/W
ØJA
3m/s air flow
—
80
—
°C/W
ESD Protection (Human Body Model)
ESDHBM
JEDEC (JESD 22-A114)
–4000
—
4000
V
ESD Protection (Charge Device Model)
ESDCDM
JEDEC (JESD 22-C101)
–1500
—
1500
V
ESD Protection (Machine Model)
ESDMM
JEDEC (JESD 22-A115)
–200
—
200
V
MSL
JEDEC (J-STD-020)
Moisture Sensitivity Level
1
Note: While using multiple power supplies, the Voltage on any input or I/O pin cannot exceed the power pin during power-up.
Power supply sequencing is not required.
Preliminary Rev. 0.7
5
Si51219
2. Design Considerations
2.1. Typical Application Schematic
VDD
10µF
0.1µF
0.1µF
VDD
VDDO
CL1
XOUT
SSCLK3
Si51219
XIN
SSCLK2
CL2
VDD
FSEL
VSS
5K
5K
Comments and Recommendations
Decoupling Capacitor: A decoupling capacitor of 0.1 μF must be used between VDD and VSS on the pins 1 and
8. Place the capacitor on the component side of the PCB as close to the VDD pin as possible. The PCB trace to the
VDD pin and to the GND via should be kept as short as possible Do not use vias between the decoupling capacitor
and the VDD pin. In addition, a 10 µF capacitor should be placed between VDD and VSS.
Series Termination Resistor: A series termination resistor is recommended if the distance between the outputs
(SSCLK or REFCLK pins) and the load is over 1 ½ inch. The nominal impedance of the SSCLK output is about
30 Ω. Use 20 Ω resistor in series with the output to terminate 50 Ω trace impedance and place 20 Ω resistor as
close to the SSCLK output as possible.
Crystal and Crystal Load: Only use a parallel resonant fundamental AT cut crystal. Do not use higher overtone
crystals. To meet the crystal initial accuracy specification (in ppm) make sure that external crystal load capacitor is
matched to crystal load specification. To determine the value of CL1 and CL2, use the following formula;
C1 = C2 = 2CL – (Cpin + Cp)
Where: CL is load capacitance stated by crystal manufacturer
Cpin is the Si51219 pin capacitance (4 pF)
Cp is the parasitic capacitance of the PCB traces.
Example: If a crystal with CL=12 pF specification is used and Cp=1 pF (parasitic PCB capacitance on PCB), 19 or 20 pF
external capacitors from pins XIN (pin 2) and XOUT (Pin 3) to VSS are required. Users must verify Cp value.
6
Preliminary Rev. 0.7
Si51219
3. Functional Descriptions
3.1. Input Frequency Range
The input frequency range is from 8.0 to 48.0 MHz for crystals and ceramic resonators. If an external clock is used,
the input frequency range is from 8.0 to 166.0 MHz.
3.2. Output Frequency Range and Outputs
Up to three outputs can be programmed as SSCLK or REFCLK. SSCLK output can be synthesized to any value
from 3 to 200 MHz with spread based on valid input frequency. The spread at SSCLK pins can be stopped by the
SSON input control pin. If SSON pin is high (VDD), the frequency at SSCLK pin is synthesized to the nominal value
of the input frequency and there is no spread.
REFCLK is the buffered output of the oscillator and is the same frequency as the input frequency without spread.
However, REFCLK_D output is divided by output dividers from 2 to 32. By using only low cost, fundamental mode
crystals, the Si51219 can synthesize output frequency up to 200 MHz, eliminating the need for higher order
crystals (Xtals) and crystal oscillators (XOs). This reduces the cost while improving the system clock accuracy,
performance, and reliability.
3.3. Programmable Modulation Frequency
The spread spectrum clock (SSC) modulation default value is 31.5 kHz. The higher values of up to 62 kHz can also
be programmed. Less than 30 kHz modulation frequency is not recommended to stay out of the range audio
frequency bandwidth since this frequency could be detected as a noise by the audio receivers within the vicinity.
3.4. Programmable Spread Percent (%)
The spread percent (%) value is programmable from ±0.25% to ±1% (center spread) for all SSCLK frequencies. It
is possible to program smaller or larger non-standard values of spread percentage. Contact Silicon Labs if these
non-standard spread percent values are required in the application.
3.5. SSON or Frequency Select (FSEL)
The Si51219 pin 4 and 6 can be programmed as either SSON to enable or disable the programmed spread percent
value or as frequency select (FSEL). If SSON is used, when this pin is pulled high (VDD), the spread is stopped
and the frequency is the nominal value without spread. If low (GND), the frequency is the nominal value with the
spread.
If FSEL function is used, the output pins can be programmed for different set of frequencies as selected by FSEL.
SSCLK value can be any frequency from 3 to 200 MHz, but the spread % is the same percent value. REFCLK is
the same frequency as the input reference clock and the REFCLK_D input clock is divided by 2 to 32 without
spread. The set of frequencies in Table 4 is given as an example, using a 48 MHz crystal.
Table 4. Example Frequencies
FSEL
(Pin 6)
SSCLK1
(Pin 4)
0
66 MHz, ±1%
1
33 MHz, ±1%
3.6. Power Down (PD) or Output Enable (OE)
The Si51219 pin 6 can be programmed as PD input. Pin 4 and pin 6 can be programmed as OE input. PD turns off
both PLL and output buffers whereas OE only disables the output buffers to Hi-Z.
Preliminary Rev. 0.7
7
Si51219
4. Pin Descriptions: 8-Pin TSSOP
VDD
1
8
XOUT
2
7 SSCLK3
XIN/CLKIN
3
SSCLK1/REFCLK
FSEL/SSEL/SSON/
OE2
4
Si51219
VDDO
6
SSCLK2/REFCLK_D
FSEL/SSEL/
SSON/PD/OE1
5
VSS
Table 5. Si51219 Pin Descriptions
8
Pin #
Name
Type
Description
1
VDD
2
XOUT
O
Crystal output. Leave this pin unconnected (floating) if an external clock
input is used.
3
XIN/CLKIN
I
External crystal and clock input.
4
SSCLK1/REFCLK/
FSEL/SSEL/SSON/
OE2
I/O
5
VSS
GND
6
SSCLK2/REFCLK_D/
OE1/FSEL/SSEL/
SSON/PD
I/O
Programmable SSCLK2 or REFCLK_D output or MultiFunction control
input. The frequency at this pin is synthesized by internal PLL if programmed as SSCLK2 with or without spread. If programmed as REFCLK_D, output clock is buffered output of crystal or reference clock
input divided by 2 to 32. If programmed as MultiFunction control input, it
can be OE, PD, FSEL, SSEL and SSON.
7
SSCLK3
O
Programmable SSCLK3 output. The frequency at this pin is synthesized
by internal PLL with or without spread. It is power by VDDO pin (pin 8).
8
VDDO
PWR 2.5 to 3.3 V power supply.
Programmable SSCLK1 or REFCLK output or MultiFunction control
input. The frequency at this pin is synthesized by internal PLL if programmed as SSCLK1 with or without spread. If programmed as REFCLK, output clock is buffered output of crystal or reference clock input. If
programmed as MultiFunction control input, it can be OE, FSEL, SSEL
and SSON.
Ground.
PWR 1.8 to 3.3 V output power supply to SSCLK3 (pin 7) VDDO ≤ VDD.
Preliminary Rev. 0.7
Si51219
5. Ordering Information
Part Number
Package Type
Temperature
Si51219-AxxxFT
8-pin TSSOP
Commercial, 0 to 70 C
Si51219-AxxxFTR
8-pin TSSOP—Tape and Reel
Commercial, 0 to 70 C
Si 51219
SiSi512xx
51210 programmable Clock
Generator Product Family
FTR
AXXX
Operating Temp Range:
F = 0 to + 70 ° C
T = TSSOP package
R = Tape & Reel
( blank) = Tubes
A = Product Revision A
2nd Option Code= XXX
A threecharacter code will be assigned for each unique configuration
.
Device starts operation upon powerup
.
Preliminary Rev. 0.7
9
Si51219
6. Package Outline: 8-pin TSSOP
10
Preliminary Rev. 0.7
Si51219
NOTES:
Preliminary Rev. 0.7
11
ClockBuilder Pro
One-click access to Timing tools,
documentation, software, source
code libraries & more. Available for
Windows and iOS (CBGo only).
www.silabs.com/CBPro
Timing Portfolio
www.silabs.com/timing
SW/HW
Quality
Support and Community
www.silabs.com/CBPro
www.silabs.com/quality
community.silabs.com
Disclaimer
Silicon Laboratories intends to provide customers with the latest, accurate, and in-depth documentation of all peripherals and modules available for system and software implementers
using or intending to use the Silicon Laboratories products. Characterization data, available modules and peripherals, memory sizes and memory addresses refer to each specific
device, and "Typical" parameters provided can and do vary in different applications. Application examples described herein are for illustrative purposes only. Silicon Laboratories
reserves the right to make changes without further notice and limitation to product information, specifications, and descriptions herein, and does not give warranties as to the accuracy
or completeness of the included information. Silicon Laboratories shall have no liability for the consequences of use of the information supplied herein. This document does not imply
or express copyright licenses granted hereunder to design or fabricate any integrated circuits. The products must not be used within any Life Support System without the specific
written consent of Silicon Laboratories. A "Life Support System" is any product or system intended to support or sustain life and/or health, which, if it fails, can be reasonably expected
to result in significant personal injury or death. Silicon Laboratories products are generally not intended for military applications. Silicon Laboratories products shall under no
circumstances be used in weapons of mass destruction including (but not limited to) nuclear, biological or chemical weapons, or missiles capable of delivering such weapons.
Trademark Information
Silicon Laboratories Inc., Silicon Laboratories, Silicon Labs, SiLabs and the Silicon Labs logo, CMEMS®, EFM, EFM32, EFR, Energy Micro, Energy Micro logo and combinations
thereof, "the world’s most energy friendly microcontrollers", Ember®, EZLink®, EZMac®, EZRadio®, EZRadioPRO®, DSPLL®, ISOmodem ®, Precision32®, ProSLIC®, SiPHY®,
USBXpress® and others are trademarks or registered trademarks of Silicon Laboratories Inc. ARM, CORTEX, Cortex-M3 and THUMB are trademarks or registered trademarks of
ARM Holdings. Keil is a registered trademark of ARM Limited. All other products or brand names mentioned herein are trademarks of their respective holders.
Silicon Laboratories Inc.
400 West Cesar Chavez
Austin, TX 78701
USA
http://www.silabs.com